Factors associated with the composition and diversity of the cervical microbiota of reproductive-age Black South African women: a retrospective cross-sectional study

PeerJ

article

Harris Onywera¹  Anna-Lise Williamson¹  Zizipho Z.A. Mbulawa¹  David Coetzee⁵  Tracy L. Meiring¹ 

[1] Institute of Infectious Disease and Molecular Medicine, University of Cape Town;Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town;SAMRC Gynaecological Cancer Research Centre, University of Cape Town;Center for HIV & STIs, National Institute for Communicable Diseases, National Health Laboratory Service, University of Cape Town;Center for Infectious Disease Epidemiology and Research, School of Public Health and Family Medicine, University of Cape Town

关键词: Cervical microbiota;    Bacterial vaginosis (BV);    Human papillomavirus (HPV);    Hormonal contraception;    Black South African;    Reproductive-age;   

DOI  :  10.7717/peerj.7488

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

BackgroundLactobacillus spp. are common bacteria in the cervical and vaginal microbiota (CVM) and are thought to represent a “healthy” cervicovaginal state. Several studies have found an independent association between ethnicity/race and cervical and vaginal microbiota (CVM) composition. Women of sub-Saharan African descent appear to be significantly more likely to have non-Lactobacillus-dominated CVM compared to women of European descent. The factors contributing to these differences remain to be fully elucidated. The CVM of Black South African women and factors influencing their CVM remain understudied. In this study, we characterized the cervical microbiota of reproductive-age South African women and assessed the associations of these microbiota with participants’ metadata.MethodsThe cervical microbiota from cervical DNA of 62 reproductive-age women were profiled by Ion Torrent sequencing the V4 hypervariable region of the bacterial 16S ribosomal RNA (rRNA) gene and analyzed with the Quantitative Insights Into Microbial Ecology (QIIME), UPARSE, and metagenomeSeq tools. Associations between cervical microbiota and participants’ metadata were assessed using GraphPad Prism, R packages and an in-house script.ResultsThe cervical microbiota clustered into three distinct community state types (CSTs): Lactobacillus iners-dominated cervical microbiota (CST I (38.7%, 24/62)), unclassified Lactobacillus-dominated cervical microbiota (CST II (4.8%, 3/62)), and diverse cervical microbiota (CST III (56.5%, 35/62)) with an array of heterogeneous bacteria, predominantly the bacterial vaginosis (BV)-associated Gardnerella, Prevotella, Sneathia, and Shuttleworthia. CST III was associated with BV (p = 0.001). Women in CST I were more likely to be on hormonal contraception, especially progestin-based, compared to women in CST III (odds ratio: 5.2 (95% CI [1.6–17.2]); p = 0.005). Women on hormonal contraception had a significantly lower alpha (Shannon indices: 0.9 (0.2–1.9) versus 2.3 (0.6–2.3); p = 0.025) and beta (permutational multivariate analysis of variance (PERMANOVA) pseudo-F statistic =4.31, p = 0.019) diversity compared to non-users. There was no significant difference in the alpha (Shannon indices: 1.0 (0.3–2.2) versus 1.9 (0.3–2.2); p = 0.483) and beta (PERMANOVA pseudo-F statistic = 0.89, p = 0.373) diversity in women with versus without human papillomavirus infection.ConclusionsThe majority of Black women in our study had non-Lactobacillus-dominated cervical microbiota. Additional studies are needed to examine whether such microbiota represent abnormal, intermediate or variant states of health. Lastly, the association of hormonal contraception with L. iners dominance requires further in-depth research to confirm this association, determine its biological mechanism and whether it has a beneficial effect on the cervicovaginal health.

【 授权许可】

CC BY